Historian names IRA mole who revealed location of Cork mayor Tomás Mac Curtain's killer

Lord Mayor of Cork Tomás Mac Curtain was murdered by the RIC on March 20, 1920.
An historian says he has unmasked the identity of an IRA mole in the RIC who informed Michael Collins of the whereabouts of a superior who had organised the murder of Cork lord mayor Tomás Mac Curtain. The superior was later assassinated in the north on Collins' orders.
Jim Herlihy, the country’s foremost chronicler of the RIC, has revealed from extensive research that Collins' spy network was far-reaching and involved a priest who passed messages between a mole in the RIC and Collins.